Under the agreement, Google’s clients will have access to the advertising inventory offered by publishers in Yandex’s Advertising Network (YAN), while Yandex’s clients will be able to bid on display ads on Google’s DoubleClick Ad Exchange. Press release.

“The perception of Yandex and Google is mostly of competition,” said Vladimir Isaev, Yandex's international media relations executive. “They’re the strongest competitors in Russia in terms of search and it’s weird when two competitors find a way to collaborate, but RTB is an example of how it can be done in a win-win situation for marketers, advertisers, and publishers.”

The RTB-based advertising market will benefit by increasing the ad inventory available to the clients of both companies and supporting the concept of open trading, said Nikolay Danilov, head of display ad services at Yandex.

“Historically, ad networks were not very popular among big advertisers in Russia,” Danilov said. “They see ad networks as an inferior source of inventory compared to the premium publishers, but that is starting to change. For Yandex, this [partnership] is another step in our development … and it will help both companies develop products to serve better adverts to customers.”

The ad inventory that is part of the deal will not include mobile or video inventory, according to Danilov. But he added it is “only a matter of time” before Yandex will offer mobile and video inventory through its RTB platform. He expects to complete the implementation within several months.

Even though Yandex and Google have teamed up on the RTB deal, Yandex continues to compete with Google. Last week, the Russian company unveiled a firmware kit for Android smartphones that allows OEMs and carriers to avoid using Google’s Android mobile OS. The Yandex.Kit includes apps and services like Yandex Search, Yandex.Mail, Yandex.Maps, the Yandex.Store and other features for Android smartphones.

Founded in 2000, Yandex dominates the search market in Russia and generated approximately $1.2 billion in total revenue in 2013. The company launched its own RTB platform in March 2012.

In Russia, Google’s ad network trails Yandex’s. YAN received approximately 60.3 million unique visitors, or 90% of the total online audience in Russia, in October 2013, according to comScore’s Media Metrix report. Google’s Display Network, by contrast, received about 58.9 million unique, or 88% of Russia’s Internet audience.